The present invention relates to a machine for machining sheet metal, and in particular to a machine featuring multiple-tool assemblies.
As is known, conventional machines are gradually being replaced by higher-output machines featuring multiple-tool assemblies which comprise a holder supporting a number of punches.
Known machines with multiple-tool assemblies comprise:
a work station in which a striking member is moved along a predetermined axis, and the portion of the member striking the tool operates along a strike axis parallel to the axis of the striking member; PA1 means for transferring the multiple-tool assembly to the work station; and PA1 means for rotating the holder of the multiple-tool assembly to align the tool with the strike axis. PA1 at least one multiple-tool assembly presenting a holder supporting a number of tools arranged in a first ring about a first vertical axis; PA1 at least one multiple-die assembly presenting a holder supporting a number of dies arranged in a second ring also about said first axis; PA1 a work station presenting a hammer movable along a second vertical axis; and PA1 a carriage for gripping and moving said sheet; PA1 characterized in that said work station comprises a striker for transmitting to the work tool the pressure exerted by said hammer; and a device for rotating said work tool about a third vertical axis consisting of its own longitudinal axis.
A major drawback of machines of the above type is the impossibility of adjusting the point of impact, so that the tools can only be used at the angle they present when aligned with the strike axis.
To orient the tool, some recently designed machines present means for rotating the striking member, and which provide for rotating the holder to orient the tool as required, and for rotating the striking member to bring the strike axis in line with the tool axis.
A major drawback of such machines is the impossibility of accurately adjusting the tool angle, due to the design of the multiple-tool assembly. That is to say, if the assembly presents eight tools, these can only be set to eight angles.